Application of Drilling Tool in Aeroengine Turning

In recent years, the global aviation industry has developed vigorously and advanced aviation products have been issued. The tool, as one of the most important subjects in the processing of aerospace components, has developed rapidly with the ever-changing aviation industry. As a leader in the domestic cutting tool industry, what is the role of drilling tools? In an interview with reporters, Zhang Jing, Zhuzhou Diamond Cutting Tool Co., Ltd. spoke of the strong alliance between aircraft drilling and aero-engine processing companies, and has made considerable progress in the field of aircraft engine turning.

Aeroengine Typical Parts Features Aeroengine typical components include: fan tray, fan casing, disk shaft, turboshaft, long shaft, integral blade and turbine casing.

Aero-engine components are typically difficult-to-machine structural components and have the following typical characteristics: 1 Extremely complex internal structures, such as deep-cavity cavities, special cutter shapes, cantilever extensions, vibrations during processing, and chip evacuation difficulties in blades The tool clearance between the tool and the workpiece needs to be fully considered when designing the tool and programming the machining program. Such as dovetail blade root groove and other poor accessibility of the groove and so on. 2 Thin-walled (weak-rigid) structure, when selecting the tool, it is necessary to fully consider the influence of cutting force on the deformation of the workpiece. 3 high dimensional accuracy requirements.

The main materials used in aero-engine parts are high-temperature alloys and titanium alloys, which are typical hard-to-machine materials. This type of material has the following characteristics: 1 large chemical activity, the formation of hardened layer at high temperatures; affinity is also large, easy to adhere with the friction surface. 2 Poor thermal conductivity, poor heat dissipation in the cutting process, resulting in a sharp increase in the temperature of the cutting edge of the tool, faster tool wear, and shorter life. 3 The elastic modulus is small, under the action of cutting force, it is easy to produce deformation. At the same time, the machined surface rebounds, causing the tool flank and the machined surface to have severe friction.

Application of Turning Tools In recent years, Zhuzhou Diamond and domestic well-known aircraft engine processing companies have worked together to develop cutting mechanism research of aerospace titanium alloys and high-temperature alloys. Combined with on-site processing technology, Zhuzhou Diamond has developed a series of professional products and constructed mature products. Aero-engine parts turning tooling system, including ISO standard turning tools, grooving tools and special-shaped non-standard tools, combined with ultrafine grain cemented carbide substrate and nano-grade PVD coating grade YBG102, to realize superalloy and titanium alloy The efficient processing.

Standard turning tools, such as NF groove series: precision grinding, high repeatability, sharp edge and tip strength, suitable for high-temperature alloy and titanium alloy finishing; NM groove series: high cutting edge strength The groove surface is smooth and the chip is smooth. It is suitable for semi-finishing and rough machining of high-temperature alloys and titanium alloys.

Taking a company's machining of a front axle of a high-pressure turbine rotor as an example, the machining material is Inconel 718, Rockwell hardness exceeds HRC39, and surface finish machining. The processing speed is about 60m/min, the processing time reaches 45min, the chip breaking is smooth, the surface is smooth, and the surface integrity of the parts is reliably guaranteed.

Grooving tools are widely used in the field of aero-engine turning, and they are also the focus of research and development of ZhuZhuang aviation tools. The ZIMF series and ZIGQ series of special grooving tools for titanium alloy superalloys were developed on the basis of the extensive market acceptance of the original "Squirrel" series of grooving tools. Single-head (edge), oblique-loading, and V-shaped were used. The positioning structure has high versatility, dimensional accuracy and repeatability. The ZIMF series insert geometry is designed with edge strength and cutting edge sharpness, excellent chip control, and low noise at high feed rates. ZIMF series is mainly used for rough machining of high-temperature alloys and titanium alloys. ZIGQ series has a sharp cutting edge, very low cutting pressure, can obtain a good surface quality, is mainly used for high-temperature alloy, titanium alloy finishing and semi-finishing.

At the same time, in order to meet the processing requirements of the complex features of typical parts of aeroengines, the drilling tools can be tailored to the customer to develop special-shaped inserts to meet various special requirements in the customer's processing.

Safe and Reliable Process Solutions The principle of the drilling engineer's custom-made process plan for the customer is precise evaluation and safety. The first consideration in the processing of aviation is its safety and reliability. The drilling engineer's customized machining solutions for customers are based on the safety of machining and the quality of the machined surface. The optimized tool path, feed, and speed are all included. On the premise of ensuring absolute safety of processing, the processing time is minimized. In the processing of the aeroengine power turbine first stage disc, the material is GH738, and the material hardness is HRC 32-42. The engineers are equipped with the following machining solutions.

The main steps for the processing of the first stage of the power turbine are as follows: crude vehicle short end, roughing vehicle long end, semi-finishing vehicle short end, semi-finishing vehicle long end, fine car reference, finisher long end, and finisher short end. In fact, the processing of the first stage of the power turbine is mainly completed by two major processes of roughing and finishing. Roughing mainly considers the strength of the blade and the high metal removal rate. The specific model of the finished insert is determined based on the size of the workpiece corner arc. Due to the complex and irregular shape of the workpiece, it is necessary to consider avoiding the air during the machining process. In the design of the process plan, the design of the special-shaped cutter bar is indispensable. Drilling tools in addition to the customer to develop an overall process plan, but also to provide customers with a single complex features required special-shaped cutting tools.

Zhuzi's new aerospace tool products and drilling tools have always taken the development and conversion of new products as the driving force for the development of enterprises, and regard technological innovation as the foundation for the survival and development of enterprises. With the development of the aerospace industry, strain drill tools have also been working hard for cutting tools for the aerospace industry. For aero-engine parts processing, it is planned to introduce a new brand, a new turning groove series and a new series of grooving tools in 2012.

For turning operations in the aero-engine field, the drilling tool is tailor-made for processing superalloys and titanium alloys with a new coating grade YBG105, which is expected to increase the life of the original YBG102 grade by more than 30%.

At present, for the characteristics of rotary parts in the aero-engine field, general-purpose NGF groove finishing turning inserts have been developed. The inserts are precision ground, and the repeat positioning accuracy is high. A complete and suitable titanium alloy and high-temperature alloy are manufactured from roughing to finishing. Groove series.

At the same time, Zhuzhuang has developed a new series of slotting knives. The convex V positioning method is used to increase the blade strength; the positioning surface of the blade adopts a fine grinding method, which improves the reliability of repeated positioning.

Drilling tools will provide customers with a complete process solution as a goal, continue to accumulate successful experience, enrich product lines, and build a complete aerospace machining tool system. It is believed that Zhuzhuang will bring more and better technical services and products to the aerospace processing industry.